Various cardiovascular procedures have been performed for many years typically by opening the sternum (referred to as a median sternotomy), and connecting the patient to cardiopulmonary bypass equipment to maintain the circulation of oxygenated blood throughout the patient's circulatory system. In this manner, the heart can be stopped and various surgical procedures performed such as coronary artery bypass grafting and replacement of aortic, mitro, and other heart valves. Numerous other surgical procedures have been performed in a similar manner.
During minimally invasive coronary artery bypass procedures using the beating heart approach, the region of the heart which receives the graft vessel must be stabilized. Presently, this is often performed by threading two suture or silicone rubber strands through the myocardium with curved needles, on either side of the recipient coronary artery at the site of the distal anastomosis. The silicone strands are tensioned to lift the heart and to hold the coronary artery stationary. Suture or silicone strands with curved needles swaged on one end are available for this use.
Placement of the suture or silicone loops may be somewhat difficult, as the heart is beating. The tip of the needle must be placed on the heart, and rotation of the surgeon's wrists must be performed to insert the needle through the myocardium. Unpredictable motion of the epicardial surface during needle placement may cause laceration of the heart or puncture of a coronary artery. It is therefore useful to stabilize the anastomotic area during the surgical procedure.
There are devices and methods that facilitate the performance of cardiac procedures such as heart valve repair and replacement, coronary artery bypass grafting, and the like, using minimally invasive techniques to eliminate the need for a gross thoracotomy. For example, U.S. Pat. No. 5,425,705 to Evard et al. discloses an apparatus and method for thoracoscopically arresting the heart and establishing cardiopulmonary bypass, thus facilitating a variety of less-invasive surgical procedures on and within the heart and great vessels of the thorax. In one embodiment, Evard provides a thoracoscopic system for arresting a patient's heart including a clamp configured for introduction into the patient's thoracic cavity through a percutaneous intercostal penetration in the patient's chest. The clamp is positionable about the patient's ascending aorta between the coronary arteries and the brachiocephalic artery. The clamp is coupled to the distal end of an elongated handle for manipulating the clamp from a location outside of the patient's thoracic cavity. It is known to use surgical clips or clamps for the purpose of clamping vessels or manipulating tissue. Typically, such clamps have a pair of movable jaws biased by a spring into a closed position, allowing the clamp to be placed on a vessel or portion of tissue and be firmly retained thereon. Examples of such clamps can be found in U.S. Pat. No. 4,932,955 to Merz et al.; U.S. Pat. No. 4,605,990 to Wilder et al.; 5,074,870 to Von Zeppelin; U.S. Pat. No. 3,809,094 to Cook; U.S. Pat. No. 4,404,677 to Springer; U.S. Pat. No. 4,051,844 to Chiulli; and U.S. Pat. No. 4,988,355 to Leveen et al.
Outside of the field of cardiac surgery, U.S. Pat. No. 5,415,666 to Gourlay et al. discloses a tethered clamp retractor used for tissue manipulation. The tissue manipulation system includes a tethered clamp, a clamp applicator for positioning the clamp through a trocar sleeve and applying the clamp to a tissue location in the abdominal cavity, and a rigid positioning shaft for engaging the clamp and/or tether to manipulate the clamp.
In view of the shortcomings of the prior art devices, there is a specific need for an apparatus and method for locally stabilizing an anastomotic site during a beating heart coronary artery grafting procedure.